Revealing mistake: There is a large painted hanging cloth backdrop of clouds in the mountain scenes near the end of the film. Vertical streaks can be seen in the backdrop that are the pleats in the fabric. These streaks really stand out in the restored versions of the film.
Continuity mistake: When Fritz is trying to steal a brain, he gets scared by a skeleton, which he grabs down, causing it to bounce up and down (since it is hanging from a hook up on the ceiling). But in the next shot, the skeleton is hardly moving. Yet when Fritz realizes he has dropped the brain, the skeleton is bouncing up and down again. (00:08:40)
Continuity mistake: When the sedative (which Dr. Waldman gives the monster in the back) kicks in, the Monster collapses to the ground, onto his back. But when Henry opens the door for Victor, the Monster is now lying facedown. (00:37:55)
Continuity mistake: During a lesson on brains, there are two jars with type-written labels ('Cerebrum - Normal Brain' and 'Disfunctio Cerebri - Abnormal). But when Fritz approaches the containers to steal the brain, the labels (Normal and Abnormal) are handwritten. (00:07:15 - 00:08:45)
Continuity mistake: After the experiment with the light, the Monster sits down on a chair, waving his hands as if he was asking for more. But in the next shot, the Monster is as still as a statue. (00:33:30)
Continuity mistake: When Henry is looking for the Monster, he finds one of the villagers, Hans, lying on the ground (after getting beat up by the Monster). Henry kneels down holding his torch with his right hand, but as he stands up, the torch is now in his left hand. (01:01:20)
Continuity mistake: Just before Victor enters Elizabeth's room, there is a shot of a picture of Henry Frankenstein, which is at the same height as a lit candle. But in the next shot, when Victor and Elizabeth walk by the table (the one on the far right of the screen) where the picture stands, the candle now appears to be much higher than the picture. (00:09:20)
Continuity mistake: At the Goldstalt Medical College, two lab assistants cover a corpse's feet with a white cloth, but in the next shot they cover the feet again. (00:06:50)